Cooling system for internal-combustion-engine pistons



E. KJORLIEN. comma SYSTEM ma INTERNAL COMBUSTION ENGINE PISTONS.

APPLICFRZIOH FILED JAN.I6,1920. 1394,84 1. Patented Oct. 25, 1921.

UNITED STATES PATENT OFFICE.

EDWIN KJORLIEN, OF MINNEAPOLIS, MINNESOTA.

Specification of Letters Patent.

Patented Oct. 25, 1921.

Application filed January 16, 1920. Serial No. 351,872.

ToaZZ whom it may concern Be it known that I, EDWIN KJoRLInN, a citizen of the United States, resident of 3545 Pleasant avenue, Minneapolis, county of Hennepin, State of Minnesota, have invented certain and useful Improvements in Cooling Systems for Internal-Combustion-Engine PistOnSQ of which the following is a specification.

This invention relates to an improvement in cooling means for internal combustion engines. It particularly relates to a means for cooling the pistons of such engines as are employed in motor vehicles and which exhibit a tendency to become heated to a temperature which interferes with the thermal efficiency of the engine.

The piston cooling is effected by means of the provision of a cooling chamber in each piston, whether the engine is of the single or of the multiple-cylindered type. A fluid is circulated through each piston chamber during the operation of the engine.

The object of this invention is to provide a cooling means for the pistons of internal combustion engines.

A more specific object is to provide a cooling chamber in the pistons of internal combustion engines and to circulate air as the cooling medium therethrough without passing through the combustion chamber of a cylinder.

Other objects of the invention will more fully appear from the following description and the accompanying drawings and will be pointed out in the annexed claims.

In the accompanying drawings there has been disclosed a structure designed to carry out the objects of this invention, but it is to be understood that the invention is not conconfined to the exact features shown as va-' rious changes may be made within the scope of the claims which follow.

In the drawings Figure 1 is a plan of a four-cylindered internal combustion engine with this invention applied, only those usual engine parts being shown which are essential to a disclosure of this invention;

Fig. 2 is a section on the line 2-2 of Fig. 1, the circulation preferably being in the direction of the arrows in Figs. 1 and 2;

Fig. 3 is a section on the line 3-3 of Fig. 2;

Fig. 4 is a partial section on the line 4-4 of Fig. 2.

In this embodiment of this invention selected for purposes of disclosure, there is shown this novel piston cooling system adapted for use with air as the circulation fluid or medium.

In this preferred construction, there are shown the usual internal combustion engine cylinders 1, each having, in accordance with standard practice, a. piston 2 provided with the usual piston ring 3. Each cylinder head, in conjunction with the combustion face of its piston, provides the usual combustion chamber 4. As each piston is similar to the others, it will be necessary to describe but one. Each piston is provided with the usual piston rod 5 and crank-shaft connection.

The piston herein, instead of having the usual solid head, is provided with an interior air chamber 6. Cooling fins 7 are provided in the air chamber which not only have the function of afi'ording additional cooling area but also have the function of strengthening the opposed sides of the air chamber. Broadly considered, there are ports opening from this air chamber on a side away from the combustion face of the piston. It is by means of these ports that the air is supplied to, and exhausted from, the air chamber. These ports are located away from the combustion face of the piston as it is not advantageous to subject these openings or connections thereto, to the compression and burning in the combustion chamber. A means adapted to cause the circulation of air is suitably connected to the cylinder block or the engine base and provided with a working connection to the ports.

In this preferred construction adapted for use with air as the cooling medium, an air duct 8 in the form of a sleeve or cylindrical pipe, extends from the air chamber. There are preferably two such pipes or ducts 8, one being employed for the air supply and the other for the air exhaust whereby heat is carried from the air chamber. Each of these air pipes extends downwardly, as shown. These two air pipes, when the engine is in operation, are subject to a reciprocating movement and hence means are provided to effect an air-tight connection with the in-' take and with the exhaust portions or this novel system.

smaller pipe.

Obviously, the air may either be forced through or drawn by a partial vacuum. The latter process is deemed preferable although transposition may be easily effected.

Each air pipe, supply and exhaust, telescopically receives one conduit of thetwo complementary series of air supply and exhaust conduits 9 in the form of a slightly Each pipe or conduit 9 carries, adjacent its telescoping end, annular packing 10 to provide a working air-tight connection. When the engine is functioning the air ducts 8 slide over the exterior of the conduits 9. In this embodiment of the invention each of the series of air supply conduits 9 has connected thereto an intake 11 opening to the atmosphere. Each of the series of exhaust conduits 9 has'con'nected thereto an exhaust pipe 12, and each of these exhaust pipes 12 is connected and communicates with an exhaust element. This exhaust element is provided with a means suitable for uniformly drawing air from each exhaust pipe. As shown, this element consists of a plurality of pipe sections of different diameters, joined to form the exhaust manifold. The series of exhaust pipes 12 successively communicate with this mani- -'fold and, after each entrant exhaust pipe,

the manifold is progressively increased in diameter to attain uniformity of air draft for each air chamber. This manifold is terminally provided with a suitable means for drawing air therefrom, such as a fan 14 adapted to be rotated from the engine shaft by means of a belt drive on the pulley 15 fast on the fan shaft 16 terminally borne by the manifold. In this novel system, means are provided for controlling the circulation of air and this is effectually accomplished by way of regulation of the air drawn through the system by the fan. An orifice 17 is provided in the exhaust manifold 13 adjacent the fan housing. A sliding valve or gate 18 is mounted on the manifold and is operable to close and open the orifice 17. The opening is formed of such area that, when the gate 18 is in open position, the fan 14 simply draws air from the atmosphere and substantially none from the cooling system. Control of the quantum of air circulatory in the system is had by variations in ?the ositions of the gate 18.

hile these air chamber openings and air ducts leading therefrom may be variously located, it is advantageous to locate them, as shown in Fig. 3, on diagonally opposite sides of the piston rod connections. It may further be noted that it is preferable to brace these ducts which may simply be effected by means of the cylindrical boss 19 on the piston and the brackets 20 interiorly extending from the piston.

There is thus provided an efiicient, and practical cooling means for internal combustion engine pistons. The parts carried by the piston are few so that the additional piston weight is minimized. An opening through the combustion chamber of the cylinder is avoided as such opening exposes the connections to the high heat of the combustion chamber and entails liability to compression leakage.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an internal combustion engine, a piston having an air chamber therein, ports opening from said chamber on a side away from the combustion face of the piston, means adapted to circulate air, means for controlling the circulation of air, and means providing a movable connection between said orts and said circulating means.

2. In a multi-cylindered internal combustion engine, each piston having an air chamber therein, a supply and an exhaust duct extending from each air chamber on the side opposite the combustion face of the piston, a series of air supply conduits connected to the supply ducts and a series of air exhaust condults connected to the exhaust ducts, air circulating means connected to one of the two series of conduits whereby air is circulated through the air chamber, and means for regulating the air circulation means whereby the circulation of air through the chambers is controlled.

In witness whereof, I have hereunto set my'hand this 18th day of December, 1919.

EDWIN KJORLIEN. 

